The strength of gravitational force is affected by the distance between objects and which of the following? Weight
Speed
Density
Mass

The gravitational force is jointly proportional to the masses of the objects involved and inversely proportional to the square of the distance between them. You've mentioned distance, so the other contributor is

1. Mass

An informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.

The answer is congress